Headlight



0. W. BLACKETT.

HEADLIGHT.

APPLICATION FIL'ED JAN. 10, 1921.

LYVEXTOR.

,1 TTORNEY.

Patented Nev. 22, 1921 PATENT OFFICE.

OLIN W. BLACKETT, 0F BROOKLINE, MASSACHUSETTS.

HEADLIGHT.

. -App1ication filed January 10, 1921.

To all whom it may concern.-

Be it known that I, OLIN WV. BLACKETT, a citizen of the United States,residing at Brookline, in the county of Norfolk and Commonwealth ofMassachusetts, have invented certain new and useful Improvements inHeadlights, of which the following is a specification.

This invention relates to headlights such als are used on automobilesand other vehi- O GS.

Suchheadlights as usually constructed, are provided with reflectorswhich project the rays of light so directed as to shine fully in theeyes of persons facing the front of the automobile, the glare of theheadlight hav inga tendency to blind or confuse them.

he object of my improvement is to limit the field of illumination andconfine the major portion of the rays of light toan area below the axisof the headlight, thus reducing and largely eliminating the glare of thelight projecting above the axis of the said light without impairing theillumination of the roadway in front of the headlight.

I attain this object in the manner illustrated in the accompanyingdrawing, in which Figure 1 is a front elevation of the headlight; Fig. 2is a central vertical section of the headlight on the line 2-2, Fig. land Fig. 3, a detail view in perspective of the non-reflectingsemi-cylindrical laminae and the radial supporting laminae.

Similar letters refer to similar parts throughout the several views. Thepara bolic reflector P, the surface of which is generated by therevolution of a. parabola about its axis through an angle of 180 degreesis palaced beneath a confocal elliptical reflector the surface of whichis generated by the revolution of an ellipse about its major axisthrough an angle of 180 degrees, the axis of the two reflectors beingcoincident, the eccentricity of the parabola and the ellipse being sotaken that the vertex of the parabola lies between the common focus andthat vertex of the ellipse which is nearest to the common focus, thesurface of the parabolic reflector meeting the surface of the ellipticalreflector at points considerably forward of the common focus. Ahorizontal crescent-shaped shelf or plate S of a suitable size joins andsupports the parabolic and elliptical reflectors, P and E. At or nearthe vertex of the. parabolic reflector P is an opening of sulfi-Specification of Letters Patent.

Patented Nov. 22, 1921.

Serial No. 436,383.

cient size and suitable shape o admit the insertion of a lightingsocket. The parabolic and elliptical reflectors P and E, extend forwardof their common focus only to the points at which their surfaces ineet,the forward ends of the said reflectors being secured to a tubular orcylindrical reflector C whose axis coincides with the axis of theheadlight. The elliptical reflector is adjusted so that the forwardfocus of the said elliptical reflector headlight, either inside oroutside of it as desired.

The front of the headlight is provided with glass G adapted to fit thesaid front and attached and adjusted thereto in any suitable manner sothat the said glass front may be 'opened and closed when desired so thatthe lamp in the interior of the headlight may be replaced. All of saidglass front above the horizontal diameter thereof is preferably ofyellow or amber color, but may be translucent, or covered with anysuitable material that will absorb partially the rays light, or pointsadjacent thereto, as desired,-

to the surface of an imaginary cone, the base of which lies at theintersection of the para? bolic and cylindrical reflectors and thevertex of which lies in the focus of the parabolic reflector, thelaminae which interfere with the light bulb in the interior of theheadlight are shortened slightly so that they will not come in contactwith the said light bulb. The semi cylindrical members are supported bynon-reflecting radial laminae R, secured to the interior surface of thecylindrical reflector. A suitable casing A. incloses the reflectors andis adapted to be fastened to the vehicle.

It will be readily seen and understood that by the arrangement of theseveral parts as shown and above described that light will be in thevicinity of the front of the the elliptical reflector is projectedthrough the forward focusonto the roadway, and the reflectors areconcealed by the translucent glass front and the laminae when observed1froliln a point in frontof and above the head aving thus described myinvention, I

claim and desire to secure by Letters Pat ent-- In a headlight, thecombination of a casing, a parabolic reflector, an ellipticalreflector,a cylindrical reflector, a source of light, said reflectorbeing adapted to throw the light ahead, a series of semi-cylindrical,nonreflecting, parallel laminae in the lower portion of the headlight, aseries of radiolaminae, supporting the semi-cylindrical laminae, and aglass front, the upper major portion of which is translucent, allsubstantially as described.

OLIN W. BLAOKETT.

